Thread: Battery life sensor

Well you normally measure the voltage across the battery with a load and see how fast the voltage is droping in time. Because a 12V reading doesnt mean your battery still have good charge when theres no load.

But wait do you mean battery life or battery remaining charge?

The basic way to do this is to use an analogue-to-digital converter. Game port do have analogue-to-digital converter, they are not very accurate but i guess they are accurate enough for this.